26.07.2022
You can find the tech behind the Webb telescope down here on Earth
NASA engineer Ernie Wright looks on as the first flight-ready mirrors for the James Webb Space Telescope are prepared to undergo testing.
David Higginbotham/NASA, MSFC
NASA's James Webb telescope has been wowing astronomers lately with stunning photos of some of the first stars in the universe — photos that capture light from more than 13 billion years ago.
But while the JWST flies through space, it's done more for us here on Earth than show images of distant galaxies. The technology developed to build the JWST has also helped improve the vision of millions of eye surgery patients.
It's one of the latest examples in a long history of NASA inventions making an impact on everyday life.
Daniel Lockney, NASA's Technology Transfer Program executive, is in charge of the program that facilitates the agency's technology spinoffs.
"Every time NASA gets asked to do a new mission, we have to come up with new technologies and new inventions in order to get it done," Lockney said. "And it's my job to make sure that those inventions come back down to Earth in the form of practical terrestrial benefits."
While building the JWST, NASA contractors developed a tool to measure the "microscopic imperfections" on its mirrors, Lockney said. That same technology has allowed eye surgeons to take precise measurements of patients' eyes before they undergo LASIK surgery.
Beyond eye surgery, there are many other things in our lives that NASA has its fingerprints on.
"NASA has contributed to everything from baby formula to cell phone cameras," Lockney said. Memory foam, temperature regulating fabrics, medical procedures, firefighter gear, cordless vacuums, precision GPS, and farming techniques are among other examples.
There are so many spinoff technologies that there is a whole website and annual publication dedicated to them.
Early in the coronavirus pandemic in 2020, NASA's Jet Propulsion Laboratory even developed a ventilator using components outside of the typical medical device supply chain, allowing it to be manufactured despite supply chain pressures.
The goals of NASA's Technology Transfer Program are written into the agency's founding legislation, but it's not the only federal agency whose inventions make it to everyday life.
"I've got thousands of examples of the technologies and advancements that were made because of the nation's investment in aerospace," Lockney said. "The federal government does a lot of R&D. We develop a lot of new technologies, and we're able to do things that don't have a profit motive. You know ... go into space or do some of the work, for example, that the NIH does into cancer research."
So while some of NASA's most famous achievements might be out in space, you don't have to look that far to find the results of the agency's work.
Quelle: npr
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Update: 27.07.2022
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JWST finds galaxies may adopt Milky Way-like shape faster than thought
Astronomers thought that galaxies in the early universe would mostly be shapeless blobs, but an analysis of data from the James Webb Space Telescope suggests around half are disc-shaped like the Milky Way
Astronomers analysing some of the first scientific data released by the James Webb Space Telescope(JWST) have already seen something they weren’t expecting. A deep view of the early universe appears to show a surprisingly high number of disc-shaped galaxies, rather than a large number of clumpy, irregular ones. This suggests that the disc structures in certain galaxies, including the Milky Way, may have formed more rapidly than current theories predict.
Quelle: NewScientist
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Update: 28.07.2022
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Scottish astronomers push James Webb deeper back in time
The Edinburgh galaxy is the latest in a succession of "most distant" observations from Webb
Scottish astronomers have spied what they believe to be the most distant galaxy ever observed, using the new super space telescope, James Webb.
The red smudge is 35 billion light-years away. We see it, as it was, just 235 million years after the Big Bang.
It's a preliminary, or "candidate", result and will need a follow-up study for confirmation.
But for the moment, the University of Edinburgh team is celebrating and marvelling at James Webb's power.
"We're using a telescope that was designed to do precisely this kind of thing, and it's amazing," said Callum Donnan, an astrophysics PhD student in the university's Institute for Astronomy.
James Webb is the $10bn successor to the Hubble Space Telescope and is hunting the first stars and galaxies to form in the 13.8-billion-year-old Universe.
These objects are extremely faint but the new observatory has been tuned specifically to pick up their glow in infrared light.
Edinburgh's high mark will almost certainly be short-lived.
Since Webb began science operations at the end of June, astronomers have been finding ever more distant candidates in its imagery.
And if the designed performance is achieved, scientists could eventually see objects with Webb that were in existence perhaps as little as 100 million years after the Big Bang.
So we should expect a succession of announcements in the weeks and months ahead.
Redshift is the term astronomers use when discussing distances in the cosmos.
It's a measure that describes the way light coming from an object has been "stretched" by the expansion of the Universe to redder wavelengths.
The higher the redshift number assigned to a galaxy, the more distant it is and the earlier it is being viewed in cosmic history.
Recent days have seen a stream of ever larger redshift numbers being reported on the popular arxiv pre-print server.
Maisie's Galaxy was found in a wide-field survey being conducted by James Webb
The last 24 hours have been a good example of how fast things can move.
The Edinburgh group pulled its target from a wide-field survey of the sky that Webb is currently conducting called the Cosmic Evolution Early Release Science (CEERS) Survey.
The team that actually runs this survey put out its own far-distant candidate on Monday called CEERSJ141946.35+525632.8.
Dubbed Maisie's Galaxy after an astronomer's daughter, this target has a redshift of 14.3, which means it's being seen about 280 million years after the Big Bang. Not quite as far as CEERS-93316 but still a remarkable prospect compared with the era before James Webb.
There is a big caveat to all this, however. The early candidates announced from Webb observations have yet to undergo full spectroscopic examination.
This process slices up the light coming from a galaxy to reveal its component colours - its spectra. These will give the clearest view of how the light, which was originally emitted at visible wavelengths, has been stretched into the infrared over the course of cosmic history.
Only after this task is completed - and Webb has the instruments to do it - will distance claims move on to a surer footing.
Another benefit of spectroscopy is that it will reveal the composition of objects.
Theory says the very first stars were fuelled just by hydrogen, helium and a small amount of lithium - the elements created in the Big Bang.
Heavier atoms - astronomers call them all "metals" - had to be forged in those pioneer stars and their descendants.
"We can look at the colours in our galaxy in a broad sense, and it's quite blue, which suggests a young stellar population. But it's not blue enough that this galaxy is made up of metal-free stars," Mr Donnan said.
It is Prof Steve Finkelstein, from the University of Texas at Austin, US, who is the proud father of Maisie.
He will be a guest on Thursday's Science In Action programme on the BBC World Service.
"I had heard a quote for this telescope that it is going to be transformative. And I said, 'you know, it's gonna do a lot of really cool things, but is it really going to completely change the way we view the Universe? I couldn't have been more wrong. Textbooks are going to be rewritten on even just the data we've gotten in the first week."
Note on distances: The Universe is expanding. In the time the light from objects takes to reach us, those objects have receded greatly. Their positions today, therefore, are much, much further away than when the light was first emitted.
Jupiter glows in new James Webb Space Telescope raw image
The observations turn Jupiter on its side.
An image of Jupiter taken by the James Webb Space Telescope on July 27, 2022. (Image credit: NASA/ESA/CSA/STScI)
Jupiter always shines, even when seen sideways in unprocessed data.
Astronomers are busy poring through new data from the James Webb Space Telescope (nicknamed Webb or JWST) in a continuing rush to spot ever-more-distant galaxies. But the observatory is continuing to study plenty of objects closer to home.
Among the targets of those observations is Jupiter. NASA released a handful of early JWST images of the massive planet on July 14, but the telescope has continued to revisit the planet thanks to a program meant to demonstrate JWST's potential to study our own solar system as well as the distant universe.
And that potential is on display in a raw image snapped by the telescope's Near Infrared Camera (NIRCam) instrument on July 27, 2022, that highlights Jupiter's massive storm, famous the Great Red Spot, as well as bands in the planet's atmosphere.
And the image, along with Webb's other observations, are designed to help scientists(opens in new tab)understand that atmosphere, tackling tasks like characterizing its thermal structure and layers, as well as studying phenomena like winds and auroras.
To create the new image, NIRCam stared at Jupiter for nearly 11 minutes using what scientists call the F212N filter, which observes light that has a wavelength of 2.12 microns, about the length of a common bacterium(opens in new tab). The filter earned its place on the observatory because scientists can use its data to study molecular hydrogen(opens in new tab).
According to a preliminary schedule(opens in new tab)released by the Space Telescope Science Institute in Maryland, which operates JWST, the observatory's targets for next week include Jupiter's volcanic moon Io, the large asteroid Hygeia and the supernova remnants Cassiopeia A.
However, observation schedules are always subject to change. In addition, not all of JWST's data is being immediately made public; for much of its observations, the scientists who requested the data get special access for one year to facilitate their analysis.
Quelle: SC
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Update: 1.08.2022
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THIN RED LINES: WEBB SPACE TELESCOPE CAPTURES STAR CREATION ON GRAND SCALE
New imagery from the James Webb Space Telescope shows a nearby galaxy in a whole new light.
This composite view shows Hubble and Webb data for the spiral galaxy NGC 7496, put together by amateur space image processor Judy Schmidt.
NASA / ESA / CSA /
Just months after its long-awaited, successful launch, the James Webb Space Telescope is already delivering on its promise. Scientific teams around the world are receiving remarkably high-resolution infrared imagery of galaxies and other worlds that are proving not only breath-taking but of great scientific interest. Janice Lee (Gemini / NSF's NOIRLab) revealed one such picture, of galaxy NGC 7496, on Twitter on July 15th.
Lee leads an international collaboration called Physics at High Angular resolution in Nearby GalaxieS (PHANGS). The program uses some of the best telescopes on ground and in space, including the Atacama Large Millimeter Array Radio Telescope and the Hubble Space Telescope, to learn about star formation.
In her recent tweet, Lee placed a Hubble image of NGC 7496 alongside a brand-new one from Webb. To the untrained eye, the second picture appears sharper and brighter, but there’s a lot more to it than that.
“Hubble captures visual light, Webb infrared, and both are needed; neither tells the whole story,” Lee says. “You can see in the first image these dark veins, where dust is obscuring part of the galaxy. In the second, we can see through the dust, for the first time with this detail, to see the bright clusters and bubbles that signify the early stages of star formation.”
The image is remarkable for showing star formation on a grand scale. The glowing, web-like shape shows the interdependent and regulating effects of star formation in large regions of space. There’s no such thing as the birth of a single star; formation is a global phenomenon. The Webb image shows evidence (in the structure of the glowing dust outlining bubbles) of both positive feedback, which compresses clouds of gas and dust to create new stars, and negative feedback, which disperses molecular clouds and interrupts star formation.
Feedback can come in the form of intense ultraviolet radiation and stellar winds. These forces act as a cosmic push and pull to both gather and disperse matter. As seen in the image above, both forces can result in shells of gas and dust around newly formed stars.
We see the effects of feedback in the glowing red lines, which represent complex molecules known as polycyclic aromatic hydrocarbons (PAHs), explains Brad Whitmore (Space Telescope Science Institute), another member of PHANGS.
“PAHs are excited by ultraviolet light from young stars and emit their energy at longer wavelengths, in the mid-infrared,” he says. “So the way this image lights up is what we hoped for and more, showing young clusters, active star forming regions, and uncovering embedded star formation.”
The PHANGS collaboration will be looking at Webb data for 19 nearby galaxies to better understand stars and star cluster formation. The early stages of the stellar cycle were previously invisible to us, blocked by dust our instruments couldn’t penetrate. Previous infrared space telescopes, including NASA’s Spitzer and ESA’s Herschel, couldn’t provide sharp-enough images for this particular task. But Webb does. Soon we will be able to test ideas about star formation and feedback in unprecedented detail.
Quelle: Sky&Telescope
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Update: 2.08.2022
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JWST reveals highly distant galaxies behind a known gravitational
magnifier
This JWST image shows the galaxy cluster SMACS J0723.3-7327 with a large number of lensed background galaxies. The white bar at the bottom corresponds to 50 arcsec, which is approximately the maximum size of Jupiter observed from Earth.
Using the first science image released by the James Webb Space Telescope (JWST) this month, an international team of scientists led by the Max Planck Institute for Astrophysics has built an improved model for the mass distribution of the galaxy cluster SMACS J0723.3-7327. They used dozens of multiple images of far-away background galaxies revealed in the JWST image, some of which were too faint to be detected previously.
Acting as a so-called gravitational lens, the foreground galaxy cluster produces both multiple images of background galaxies and magnifies these images. One family of such multiple images belongs to a galaxy, which the model predicts to be at a distance of about 13 Gyrs, i.e. whose light travelled some 13 billion years before reaching the telescope.
If confirmed, this will emphasise the importance of accurate gravitational lens models for the identification of distant galaxies and their detailed study.
The first science image released by the James Webb Space Telescope (JWST) was of a gravitational lens, in particular the galaxy cluster SMACS J0723.3-7327. Gravitational lenses, especially galaxy clusters, magnify the light from background galaxies and produce multiple images of these. Before JWST, 19 multiple images of six background sources were known in SMACS J0723.3-7327. The JWST data now revealed 27 additional multiple images from another ten lensed sources.
"In this first step towards the road opened by JWST, we used recent data from this brand new telescope, to model the lensing effect of SMACS0723 with great accuracy," points out Gabriel Bartosch Caminha, postdoc fellow at the Max Planck Institute for Astrophysics (MPA), the Technical University Munich, and the German Centre for Cosmological Lensing (GCCL).
The collaboration first used data from the Hubble Space Telescope (HST) and Multi Unit Spectroscopic Explorer (MUSE) to build a "pre-JWST" lens model, and then refined it with newly available JWST near-infrared imaging. "The JWST imaging is absolutely astounding and beautiful, showing many more multiply lensed background sources, which allowed us to substantially refine our lens mass model," he adds.
Many of these new, lensed sources do not yet have distance estimates, and the scientists used their mass model to predict how far away these lensed galaxies are most likely to be. One of them was found to be probably at the amazing distance of 13 Gyrs (redshift > 7.5), i.e. its light was emitted during the Universe's early stages. This galaxy is multiply lensed into three images and its luminosity is magnified by a factor of u"20 in total.
However, to study these primordial objects, it is fundamental to describe accurately the lensing effect of the foreground galaxy cluster.
"Our accurate mass model forms the foundation for the exploration of the JWST data," emphasizes Sherry Suyu, Max Planck Research Group Leader at MPA, an Associate Professor at the Technical University of Munich, and a Visiting Scholar at the Academia Sinica Institute of Astronomy and Astrophysics. "The spectacular JWST images show a great variety of strongly lensed galaxies, which can be studied in detail thanks to our accurate model."
The new model for the mass distribution of the foreground cluster is capable of reproducing the positions of all multiple images with a high accuracy, making the model one of the most accurate available. For follow-up studies of these sources, the lens models, including magnification maps and redshifts (i.e. distances) estimated from the model are made publicly available.
"We are very excited about this," Suyu adds, "we are eagerly awaiting future JWST observations of other strong lensing galaxy clusters. These will not only allow us to better constrain the mass distributions of galaxy clusters, but also to study high-redshift galaxies."
Quelle: SD
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Update: 4.08.2022
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Webb Captures Stellar Gymnastics in The Cartwheel Galaxy
NASA’s James Webb Space Telescope has peered into the chaos of the Cartwheel Galaxy, revealing new details about star formation and the galaxy’s central black hole. Webb’s powerful infrared gaze produced this detailed image of the Cartwheel and two smaller companion galaxies against a backdrop of many other galaxies. This image provides a new view of how the Cartwheel Galaxy has changed over billions of years.
The Cartwheel Galaxy, located about 500 million light-years away in the Sculptor constellation, is a rare sight. Its appearance, much like that of the wheel of a wagon, is the result of an intense event – a high-speed collision between a large spiral galaxy and a smaller galaxy not visible in this image. Collisions of galactic proportions cause a cascade of different, smaller events between the galaxies involved; the Cartwheel is no exception.
The collision most notably affected the galaxy’s shape and structure. The Cartwheel Galaxy sports two rings — a bright inner ring and a surrounding, colorful ring. These two rings expand outwards from the center of the collision, like ripples in a pond after a stone is tossed into it. Because of these distinctive features, astronomers call this a “ring galaxy,” a structure less common than spiral galaxies like our Milky Way.
The bright core contains a tremendous amount of hot dust with the brightest areas being the home to gigantic young star clusters. On the other hand, the outer ring, which has expanded for about 440 million years, is dominated by star formation and supernovas. As this ring expands, it plows into surrounding gas and triggers star formation.
Other telescopes, including the Hubble Space Telescope, have previously examined the Cartwheel. But the dramatic galaxy has been shrouded in mystery – perhaps literally, given the amount of dust that obscures the view. Webb, with its ability to detect infrared light, now uncovers new insights into the nature of the Cartwheel.
The Near-Infrared Camera (NIRCam), Webb’s primary imager, looks in the near-infrared range from 0.6 to 5 microns, seeing crucial wavelengths of light that can reveal even more stars than observed in visible light. This is because young stars, many of which are forming in the outer ring, are less obscured by the presence of dust when observed in infrared light. In this image, NIRCam data are colored blue, orange, and yellow. The galaxy displays many individual blue dots, which are individual stars or pockets of star formation. NIRCam also reveals the difference between the smooth distribution or shape of the older star populations and dense dust in the core compared to the clumpy shapes associated with the younger star populations outside of it.
Learning finer details about the dust that inhabits the galaxy, however, requires Webb’s Mid-Infrared Instrument (MIRI). MIRI data are colored red in this composite image. It reveals regions within the Cartwheel Galaxy rich in hydrocarbons and other chemical compounds, as well as silicate dust, like much of the dust on Earth. These regions form a series of spiraling spokes that essentially form the galaxy’s skeleton. These spokes are evident in previous Hubble observations released in 2018, but they become much more prominent in this Webb image.
Webb’s observations underscore that the Cartwheel is in a very transitory stage. The galaxy, which was presumably a normal spiral galaxy like the Milky Way before its collision, will continue to transform. While Webb gives us a snapshot of the current state of the Cartwheel, it also provides insight into what happened to this galaxy in the past and how it will evolve in the future.
The James Webb Space Telescope is the world's premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.